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Cases
Computer cases (or chassis) protect the internal components of a PC from the outside environment and come in two varieties-desktop and tower. Desktop computer cases lie on a desk with the monitor sitting on top. These were the first type of PCs and there are a few that exist today. Towers stand upright. However, the term desktop is now used to describe any system that is not a laptop. Towers are the most popular and there are three types: mini, mid, and full. The front of the case is called the bezel. Each one is designed for a certain motherboard form factor. The mini case can also be a slim tower or a HTPC. HTPC stands for Home Theater PC. As the name implies, HTPC cases are specifically designed to match your audio/video system equipment. Most lie flat like a desktop and support a micro ATX or ITX board. The mid tower and full tower support micro as well as regular ATX. When choosing tower computer cases, consider these factors:
Space - Don't have much room to spare? You may want a mini tower case. These computer cases take up very little space and can be tucked away nicely. However, at some point you may want to fix or add components to your PC. If so, then a mid or full tower case is better because they provide more space inside to work.
Computer cases (or chassis) protect the internal components of a PC from the outside environment and come in two varieties-desktop and tower. Desktop computer cases lie on a desk with the monitor sitting on top. These were the first type of PCs and there are a few that exist today. Towers stand upright. However, the term desktop is now used to describe any system that is not a laptop. Towers are the most popular and there are three types: mini, mid, and full. The front of the case is called the bezel. Each one is designed for a certain motherboard form factor. The mini case can also be a slim tower or a HTPC. HTPC stands for Home Theater PC. As the name implies, HTPC cases are specifically designed to match your audio/video system equipment. Most lie flat like a desktop and support a micro ATX or ITX board. The mid tower and full tower support micro as well as regular ATX. When choosing tower computer cases, consider these factors:
Space - Don't have much room to spare? You may want a mini tower case. These computer cases take up very little space and can be tucked away nicely. However, at some point you may want to fix or add components to your PC. If so, then a mid or full tower case is better because they provide more space inside to work.
Power Supplies
The power supply (power supply unit or PSU) is a rectangular box with several cables that fits in the top back of the case. Its primary purpose is converting AC power from an outlet to DC power the computer can use. The cables have connectors on the ends which supply different voltages to various internal components with the main connector plugging into the motherboard. However some, called modular power supplies, contain built-in connectors so you can use only the cables that are necessary.
The power supply (power supply unit or PSU) is a rectangular box with several cables that fits in the top back of the case. Its primary purpose is converting AC power from an outlet to DC power the computer can use. The cables have connectors on the ends which supply different voltages to various internal components with the main connector plugging into the motherboard. However some, called modular power supplies, contain built-in connectors so you can use only the cables that are necessary.
Power supplies conform to the ATX factor and come in a range of different wattages - from less than 300W to more than a 1000W. Which should you buy? Depends on what type of system you have. For the average system with one or two hard drives, a DVD drive, dual core CPU, and a low-end graphics card, I would suggest at least a 500W PSU. If you plan on adding more drives, get a unit that can handle the job. Better yet, go ahead and buy a 600 or 700 watt just in case upgrading is in your future. Very powerful machines such as gaming systems can use power supplies that are 1000W or more. Motherboards designed for SLI or Crossfire have PSUs specifically made for them. After purchasing, make sure the voltage is set to the correct number by using the voltage selector (100-120V for N. America. & 220-240V for Europe). Thermal Take, Cool Max, and Cooler Master are just some of the major manufacturers of PSUs.
Mid & Tall Tower Cases
Number of Drive Bays - Drive bays are where you insert hard drives and CD/DVD drives. Full tower computer cases usually contain far
more external and internal bays than mid or mini. Make sure you purchase a case with enough bays for present and future needs.
Number of Ports & Slots - Cases come equipped with a number of front panel audio, USB, and Firewire ports as well as slots in the back for expansion cards. Just like above, get the one that's suitable for your needs.
Number of Fans & Vents - Make sure the case has sufficient air flow. The more fans the better and many cases have additional vents on the side.
Case Material - Most cases are made of aluminum, steel, or both. Sometimes the bezel is plastic.
Power Supply - Many cases come with a power supply already installed. This can be a money saver instead of buying them separately.
Besides providing protection for parts, computer cases come in a multitude of stylish designs and colors. Many have a clear side and LED lighting so you can see inside. Remember to keep upgrading in mind. If you're thinking about adding extra drives or cards later, buy a case with plenty of space that supports those extra components.
more external and internal bays than mid or mini. Make sure you purchase a case with enough bays for present and future needs.
Number of Ports & Slots - Cases come equipped with a number of front panel audio, USB, and Firewire ports as well as slots in the back for expansion cards. Just like above, get the one that's suitable for your needs.
Number of Fans & Vents - Make sure the case has sufficient air flow. The more fans the better and many cases have additional vents on the side.
Case Material - Most cases are made of aluminum, steel, or both. Sometimes the bezel is plastic.
Power Supply - Many cases come with a power supply already installed. This can be a money saver instead of buying them separately.
Besides providing protection for parts, computer cases come in a multitude of stylish designs and colors. Many have a clear side and LED lighting so you can see inside. Remember to keep upgrading in mind. If you're thinking about adding extra drives or cards later, buy a case with plenty of space that supports those extra components.
Power Protection:The Uninterruptible Power Supply
If you're using a computer and there is a power outage, physical damage can occur as well as losing your data. Many users have surge protectors that guard against a sudden increase of electricity (above the standard 120 volts) that could possibly harm components, but they do not prevent data loss. Moreover, depending on how strong the surge, even a regular surge protector may not protect from extensive physical damage.
An uninterruptible power supply (UPS) is an external box containing a battery that provides power to a computer and other electronics in case there is a loss of power. There are two types: standby (offline) and online.
A standby UPS uses regular AC power from a wall outlet for a computer. When a problem arises, it immediately switches (usually under 5 milliseconds) to the battery using an inverter so the PC will not lose power and can be shut down properly. The battery charges as long as the unit connects to AC power. With an online UPS, the computer is constantly using the battery, which is continuously recharged. As a result, there is no switch over time as with a standby. The DC power produced by the charger is converted to AC by the inverter. This is an on-going cycle. During a power failure, the battery sends power to the inverter. These types are also called a true UPS.
A standby UPS is much cheaper than an online and is mostly used for homes and small offices.
An uninterruptible power supply (UPS) is an external box containing a battery that provides power to a computer and other electronics in case there is a loss of power. There are two types: standby (offline) and online.
A standby UPS uses regular AC power from a wall outlet for a computer. When a problem arises, it immediately switches (usually under 5 milliseconds) to the battery using an inverter so the PC will not lose power and can be shut down properly. The battery charges as long as the unit connects to AC power. With an online UPS, the computer is constantly using the battery, which is continuously recharged. As a result, there is no switch over time as with a standby. The DC power produced by the charger is converted to AC by the inverter. This is an on-going cycle. During a power failure, the battery sends power to the inverter. These types are also called a true UPS.
A standby UPS is much cheaper than an online and is mostly used for homes and small offices.
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